Author Topic: Hoglet timing  (Read 874 times)

Offline Trevorc

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Hoglet timing
« on: January 02, 2018, 11:42:46 AM »
Hello and a Happy New Year.
I am nearing the point of final assembly and timing the engine. I am trying to understand the sequence of valve events and sparks to help me with the timing process.
So far i cant get my brain around the problem- comes with age!!
I have a simple questions
Does anybody know if there are any errors in the drawings, relating to cam profile or magnet positions on the drive gear, published by Model Engine Builder some years go.
If i can eliminate that possibility then it my brain that needs sorting,,
Trevorc

Offline ozzie46

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Re: Hoglet timing
« Reply #1 on: January 02, 2018, 01:42:24 PM »
I've built 5 of these and here is what I found on the net for timing of the Hoglet.


Timing the cam to the crank
1. Have you made a mark on the flywheel to measure when the front piston is Top Dead Center? If not, now would be a good time. Rotate the crank so the front piston is TDC. You can find TDC by sticking a dial indicator through the spark-plug hole. Make a calibration mark on the flywheel. Now rotate the crank 90 degrees (Clockwise when viewed from the cam side) - it is now half way through the stroke. This is where the valve should be wide open.
 
2. Make sure the tapered screw that locks the gear on the crank is loose. Put a dial indicator on the front intake valve lifter. Now, by spinning the gear on the crank, find the highest point of lift. Lock the gear on the crank. Done!
 
Timing the Ignition
Rotate the engine so the front piston is at TDC at the start of the power stroke. Now move the timing lever till you get a spark. The engine will now fire TDC which will cause the engine to run. Once it is running you can fine-tune the spark timing to give the best performance.

 instructions from Clarence Elias as posted by Camm-1

Ron

Offline fumopuc

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Re: Hoglet timing
« Reply #2 on: January 02, 2018, 07:26:38 PM »
Hi Trevorc,
my Hoglet timing was done 3 weeks ago exactly as posted by Ron.
Engine is running quite well.
I couldn't notice any errors in the MEB plan set.
Kind Regards
Achim

Offline Trevorc

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Re: Hoglet timing
« Reply #3 on: January 02, 2018, 08:01:23 PM »
Thank you gentlemen for your help.
Now i know that its my brain that has some problems!! I dont mind that, what i dont like is making something to a drawing only to learn later that there are errors. This was a fairly common problem with model steam loco drawings.
What a marvellous  thing this MEM forum is. Replies from Germany and USA have put my mind at rest.
Many thanks
Trevorc